In the related art, a configuration is known in which an ISOFIX anchor as an attachment tool for fixing a child seat is provided in a rear seat surface of a vehicle seat (for example, see JP-A-2015-085730). The ISOFIX anchor is provided in the state of being embedded in a hole which is formed though a portion formed in a rear end portion of a seat cushion and bulging in a bank shape. The embedded hole of the ISOFIX anchor is normally configured such that a front-side opening is covered with a cover member which is openable and closable. When the child seat is mounted, the cover member is opened so that the ISOFIX anchor therein is exposed to a front side.
In the above-described related art, the embedded hole of the ISOFIX anchor is covered from the front side in appearance with the cover member. However, in the cover member, in a case where cooling air of a battery flows in a back-side area of the seat, it cannot be appropriately prevented that the cooling air flows to leak out through the hole to the seat front side.